The URL validation functionality in Microsoft Internet Explorer 5.01, 6, 6 SP1, 7 and 8, and the ShellExecute API function in Windows 2000 SP4, XP SP2 and SP3, and Server 2003 SP2, does not properly process input parameters, which allows remote attackers to execute arbitrary local programs via a crafted URL, aka "URL Validation Vulnerability."

Microsoft Internet Explorer 6, 6 SP1, 7, and 8 does not properly handle objects in memory, which allows remote attackers to execute arbitrary code by accessing an object that (1) was not properly initialized or (2) is deleted, leading to memory corruption, aka "Uninitialized Memory Corruption Vulnerability," a different vulnerability than CVE-2009-2530 and CVE-2009-2531.

Use-after-free vulnerability in the CRecalcProperty function in mshtml.dll in Microsoft Internet Explorer 5.01 through 7 allows remote attackers to execute arbitrary code by calling the setExpression method and then modifying the outerHTML property of an HTML element, one variant of "Uninitialized Memory Corruption Vulnerability."